1. Field of the Invention
The invention relates generally to the field of treatment of occluded infection collections, abscesses, inflamed and/or diseased projections in pouch-like portions of the digestive tract, such as an appendix or a diverticular abscess or diverticulum, and more specifically to devices and methods that provide an opening to drain inflamed anatomical structures in the digestive tract without resorting to open surgery or to removal of the anatomical structures.
2. Description of the Related Art
The appendix is a small, tube-like structure attached to the first part of the large intestine, also called the colon. The appendix is typically located in the lower right portion of the abdomen. Removal of the appendix appears to cause no change in digestive function. Appendicitis (or epityphlitis) is an inflammation of the appendix. The cause of appendicitis relates to blockage of the inside of the appendix, known as the lumen. The blockage leads to increased pressure, impaired blood flow, and inflammation. If the blockage is not treated, gangrene and rupture (breaking or tearing) of the appendix can result. Most commonly, feces or calcification blocks the inside of the appendix. Also, bacterial or viral infections in the digestive tract can lead to swelling and inflammation, which squeeze the appendix and cause obstruction to the more distal appendix. This swelling of lymph nodes is known as lymphoid hyperplasia. Traumatic injury to the abdomen may lead to appendicitis in a small number of people. Genetics may be a factor in others. For example, appendicitis that runs in families may result from a genetic variant that predisposes a person to obstruction of the appendiceal lumen.
In the past, appendicitis has lacked an effective medical therapy, so appendicitis is often considered a medical emergency. While some try to treat it with antibiotics, drug-only therapy techniques have had somewhat limited success. Prior treatment of appendicitis required the removal of the appendix by open surgery, laparotomy or laparoscopy. An appendicectomy (or appendectomy) is normally performed as an emergency procedure, when the patient is suffering from acute appendicitis. When treated promptly, most patients recover without difficulty. If treatment is delayed, the appendix can burst, causing infection and even death. Appendicitis is the most common acute surgical emergency of the abdomen.
X rays, ultrasound, and computed tomography (CT) scans can produce images of the abdomen. Plain x rays can show signs of obstruction, perforation (a hole), foreign bodies, and in rare cases, an appendicolith, which is a calcification in the appendix. Ultrasound may show appendiceal inflammation or fluid and can diagnose gall bladder disease and pregnancy. By far the most common test used, however, is the CT scan. This test provides a series of cross-sectional images of the body and can identify many abdominal conditions and facilitate diagnosis when the clinical impression is in doubt. In selected cases, MRI may be used and particularly in women when the cause of the symptoms may be either the appendix or an inflamed ovary or fallopian tube, laparoscopy may be necessary. Laparoscopy avoids radiation, but requires general anesthesia.
The most serious complication of appendicitis is rupture. The appendiceal wall bursts or tears if appendicitis is not diagnosed quickly and goes untreated. Infants, young children, and older adults are at highest risk. A ruptured appendix can lead to peritonitis and abscess. Peritonitis is a dangerous infection that happens when bacteria and other contents of the torn appendix leak into the abdomen. In people with appendicitis, an abscess usually takes the form of a swollen mass filled with fluid and bacteria. In a few patients, complications of appendicitis can lead to organ failure and death.